Arrangement and method for forming doctor blade blanks for use with a roll in a paper/board machine

ABSTRACT

Arrangement and method for handling doctor blades of a paper/board machine which are placed against a face of a roll in the paper/board machine to keep the face clean and to service the face. A doctor blade blank is formed from a doctor blade roll, i.e., from a reel of doctor blade material, by unwinding the roll of doctor blade material and cutting the doctor blade material at a determined cut-off point to thereby obtain a doctor blade blank having a desired pullout or blade length and which will be modified to form a doctor blade.

CROSS REFERENCE TO RELATED APPLICATION

[0001] The present application is a divisional application of copendingU.S. patent application Ser. No. 09/263,397 filed Mar. 5, 1999

FIELD OF THE INVENTION

[0002] The present relates to an arrangement and method for formingdoctor blade blanks for use for a roll in a paper/board machine. Thepresent invention relates to an arrangement and method for handlingdoctor blades for a roll in a paper/board machine.

BACKGROUND OF THE INVENTION

[0003] In the prior art, the use of various doctor blades in a paper orboard machine is known. A doctor blade is an important part of a paperor board machine which secures the operation of the paper/board machine,i.e., ensures its operability. The blade is typically arranged inconnection with a roll and maintains the condition of the roll face andremoves a web portion from the roll face which is then passed out ofconnection with the roll into a pulper.

[0004] As is well known in the art, doctor blades have been stored inconnection with the paper/board machine on various shelves for doctorblades. For use, the doctor blade is lifted from the shelf straight intoa doctor blade holder construction.

OBJECTS AND SUMMARY OF THE INVENTION

[0005] It is an object of the present invention to provide a new andimproved arrangement and method for handling doctor blades.

[0006] It is another object of the present invention to provide a newand improved arrangement and method for the storage and preparation ofdoctor blades for a paper/board machine.

[0007] It is another object of the present invention to provide new andimproved arrangements and methods for forming doctor blade blanks forsubsequent use as doctor blades.

[0008] In order to achieve these objects, and others, in accordance withthe invention, a separate storage carriage is employed, which comprisesat least one roll of doctor blades from which the doctor blade can beunwound, i.e., a reel of doctor blade material. The doctor bladematerial placed on the roll can be unwound through a separatemeasurement device and associated cut-off device. The cut-off devicecomprises a measurement detector from which the pulled-out length of thedoctor blade and the residual length remaining in the roll can bemeasured and read. At a desired point, the feed of the doctor blade fromthe roll is stopped, and the doctor blade is cut off to the desiredlength. The roll of doctor blades is arranged around a revolvinglymounted shaft and the band of doctor blades is passed through separateguides to the cut-off device. A measurement detector of the measurementdevice is placed in direct vicinity of the cut-off device and measuresthe blade length that has been fed. From a display placed in connectionwith a central processing unit, it is possible to read the blade lengththat has been fed out, and further, from the display it is possible toread the blade length that remains on the roll of doctor blades.

[0009] The roll of doctor blades is placed in a separate carriage, whichcan be shifted into different locations in connection with thepaper/board machine. Thus, the same carriage can be used in differentlocations while the carriage comprises a number of different rolls ofdoctor blades and separate cut-off means and measurement detectors forthe rolls of doctor blades.

[0010] Thus, in one embodiment of an arrangement for forming doctorblade blanks from at least one roll of doctor blade material, holdingmeans, e.g., a storage carriage, is provided to hold each roll of doctorblade material such that the doctor blade material is unwindabletherefrom and cutting means for cutting each roll of doctor bladematerial after the doctor blade material has been at least partiallyunwound from the roll to form a doctor blade blank having a desiredlength. Preferably, the length of the doctor blade material beingunwound from each roll is measured by measurement means, e.g., ameasurement detector arranged in connection with each roll. The centralprocessing unit is coupled to the measurement means, e.g., by a datatransfer bus, for receiving the measured length of the doctor bladematerial being unwound from each roll and is arranged to enable thecutting means to be manually or automatically actuated to cut thedesired length of doctor blade material from each roll. To this end, adisplay is coupled to the central processing unit, e.g., by a datatransfer bus, for displaying the measured length of the doctor bladematerial being unwound from each of the at least one roll.

[0011] The carriage may include one or more compartments, each rollbeing situated in a respective compartment, and an opening associatedwith each compartment through which the doctor blade material from theroll situated in that compartment is unwound. The measurement means,e.g., a measurement detector arranged in each compartment at orproximate the opening, thereby measures the length of doctor bladematerial being unwound from the roll situated in the compartment andpassed through the opening. The cutting means, e.g., a cut-off device,are also arranged proximate the opening of each compartment and guidemeans are associated with each compartment for guiding unwinding of thedoctor blade material through the opening.

[0012] In the method for forming doctor blade blanks from at least oneroll of doctor blade material, the doctor blade material is unwound fromthe roll(s), the length of the doctor blade material being unwound ismeasured, a cut-off point on each roll of doctor blade material isdetermined in order to obtain a doctor blade blank having a desiredlength, the unwinding of the doctor blade material is stopped once thedoctor blade material has been unwound past the cut-off point, and thenthe doctor blade material is cut at the cut-off point to thereby form adoctor blade blank having the desired length. This procedure is repeatedwhen necessary to enable the formation of multiple doctor blade blanksfrom a single roll of doctor blade material.

[0013] In the following, the invention will be described in detail withreference to some exemplifying embodiments of the invention illustratedin the figures in the accompanying drawing. However, the invention is byno means strictly confined to the details of the illustrated embodimentsalone.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The following drawings are illustrative of embodiments of theinvention and are not meant to limit the scope of the invention asencompassed by the claims.

[0015]FIG. 1 is a perspective view of a storage carriage for rolls ofdoctor blades in accordance with the invention.

[0016]FIG. 2 is a schematic illustration of a roll of doctor blades inaccordance with the invention.

[0017]FIG. 3 is a schematic illustration of the operation of anarrangement in accordance with the invention as a block diagrampresentation.

DETAILED DESCRIPTION OF THE INVENTION

[0018] Referring to the accompanying drawings wherein the same referencenumerals refer to the same or similar elements, FIG. 1 is a perspectiveview of a storage carriage for rolls of doctor blades including separatecompartments (also referred to as stations or positions) for differentreels or rolls of doctor blades as well as, for each reel or roll,separate cut-off devices for cutting the reels or rolls to form doctorblades and measurement detectors for measuring the length of the doctorblade. The doctor blades formed from the roll or reel of doctor bladematerial can also be called doctor blade blanks, because a length ofdoctor blade material that has been cut off to the specified measure isusually provided with perforations and required fastenings and only thenwould constitute a doctor blade useable in a paper/board machine. Onceprovided with perforations and fastenings, the doctor blade is installedin connection with a roll in the paper/board machine.

[0019] More specifically, FIG. 1 shows a storage carriage 50 for rollsof doctor blades 10 a ₁, 10 a ₂, 10 a ₃ which comprises a box-like frameR, an upper, openable lid R₁ and a side cover R₂. Wheels 50 a ₁,50 a₂,50 a ₃,50 a ₄ (of which only 50 a ₄ is not shown) are provided on alower surface of the frame R to enable the carriage 50 to be moved todifferent locations in the paper/board machine. The rolls of doctorblades 10 a ₁, 10 a ₂ and 10 a ₃ are placed in compartments D₁, D₂ andD₃, respectively, inside the frame R. Although three compartments areshown, it should be understood that the frame R may contain any numberof compartments. Each roll of doctor blades 10 a ₁, 10 a ₂, 10 a ₃ isrotatably mounted on a shaft 11 which is revolvingly mounted on bearings12 a ₁, 12 a ₂. Measurement device 13 includes a measurement detector 13a ₁ arranged in connection with the feed-out opening A₁ of thecompartment D₁ of the doctor blade roll 10 a ₁ for measuring the lengthof a doctor blade T to be formed. Cut-off device 14 a ₁ and at least oneguide 15 a ₁, 15 a ₁′, . . . (shown in FIGS. 2 and 3) are also arrangedin connection with the feed-out opening A₁. Based on a measurementsignal produced by means of the measurement detector 13 a ₁, thefeed-out length of the doctor blade T that has been fed out and also theresidual length remaining on the roll 10 a ₁, are computed in a centralprocessing unit 100, and the measurement data can be read from a display16 connected to the central processing unit. When the desired/estimatedfeed-out length of the doctor blade T has been reached, unwinding of thedoctor blade material is stopped and the cut-off device 14 is operatedand the doctor blade T is cut off. In a corresponding manner,compartments D₂ and D₃ comprise similar arrangements for the doctorblade rolls 10 a ₂, 10 a ₃, respectively, associated with thecompartments. The feed-out length of the doctor blade T can also beestimated, in which case a measurement device is not required.

[0020]FIG. 2 is a schematic illustration of a roll of doctor blades,i.e., a reel of doctor blades 10 a ₁, 10 a ₂, 10 a ₃, in accordance withthe invention, wherein each roll or blank of a doctor blade is mountedon a shaft, which is provided with bearings. In the vicinity of thefeed-out end of each doctor blade, there is the measurement detector andcut-off device. In the vicinity of each feed-out opening, there is alsothe guide for the doctor blade.

[0021] More specifically, FIG. 2 shows doctor blade roll compartmentsD₁, D₂, D₃, each including a shaft 11 a ₁, 11 a ₂, 11 a ₃ for a roll ofdoctor blades 10 a ₁, 10 a ₂, 10 a ₃, bearings 12 a ₁, 12 a ₂ mounted onthe shaft 11 a ₁, 11 a ₂, 11 a ₃, a feed-out opening A₁, A₂, A₃ and ameasurement detectors 13 a ₁, 13 a ₂, 13 a ₃ arranged in connection withthe feed-out opening A₁,A₂,A₃. Display 16 is arranged to display themeasurement information produced from each compartment D₁, D₂, D₃. Thecentral processing unit 100 interposed between the measurement device 13and the display 16 operates as a collector/processor of the data fromthe measurement device 13, i.e., from the measurement detectors 13 a,and directs the measurement data along a bus e₄ to the display 16. Themeasurement data is obtained based on the information produced by themeasurement detectors 13 a ₁, 13 a ₂, 13 a ₃. The cut-off device 14 a ₁,14 a ₂ and 14 a ₃ of each station D₁, D₂, D₃ performs the cutting-off ofthe doctor blade T based on the data read from the display 16. Thecutting-off can be carried out by the operator of the carriage 50. Inaddition to the cut-off device, the arrangement in accordance with theinvention can also include a perforation device 200, by whose meanspull-out holes can be perforated to the end/ends of the doctor blade(FIG. 2). The perforation device 200 may be arranged in connection withthe cut-off devices 14 a, or it may be a separate device which isindependent from the cut-off devices 14 a and which is displaceable tothe desired compartment D₁, D₂, D₃.

[0022] Further, the central processing unit 100 optionally includecontrols for the operation of the cut-off devices 14 a ₁, 14 a ₂, 14 a₃, i.e., the cut-off devices 14 a are coupled to the central processingunit, e.g., by electrical cables. Such controls may be arranged, forexample in connection with the lid R₁ of the carriage 50. Similarly, thedisplay 16 can be placed in connection with the lid R₁.

[0023]FIG. 3 is a block diagram of the operation of the arrangement inaccordance with the invention which is used in a method in accordancewith the invention. From the measurement detectors 13 a ₁, 13 a ₂ or 13a ₃ of the compartments D₁, D₂, D₃, the measurement information ispassed along data transfer buses e₁, e₂, e₃ to the central processingunit 100, and further from the central processing unit 100 there is adata transfer bus e₄ to the display 16 for reading of the information ofthe compartments D₁, D₂ and/or D₃. Optionally, it is possible to readthe length of the blade T that has been pulled out of the opening A₁, A₂and/or A₃, in which case, the cut-off device 14 a ₁, 14 a ₂ and/or 14 a₃ can be operated when the desired pull-out length has been reached.From the display 16, it is also possible to read, in respect of eachcompartment D₁, D₂, D₃, the remaining blade length of the doctor bladeroll 10 a ₁, or 10 a ₂ or 10 a ₃ placed in the respective compartment.The guides 15 a ₁, 15 a ₁′, . . . , 15 a ₂, 15 a ₂′, . . . , 15 a ₃, 15a ₃′, . . . controls the path of the blade T in a controlled manner pastthe measurement detector 13 a ₁, 13 a ₂, 13 a ₃ of each compartment D₁,D₂, D₃ and further past the cut-off device 14 a ₁, 14 a ₂, 14 a ₃related to the compartment D₁, D₂, D₃.

[0024] The examples provided above are not meant to be exclusive. Manyother variations of the present invention would be obvious to thoseskilled in the art, and are contemplated to be within the scope of theappended claims.

We claim:
 1. An arrangement for forming doctor blade blanks from atleast one roll of doctor blade material, comprising holding means forholding each of the at least one roll of doctor blade material such thatthe doctor blade material is unwindable from the roll, and cutting meansfor cutting each of the at least one roll of doctor blade material afterthe doctor blade material has been at least partially unwound from theroll to form a doctor blade blank having a desired length; wherein saidholding means comprise a carriage including at least one compartment,each of said at least one roll being situated in a respective one ofsaid at least one compartment, said carriage including an openingassociated with each of said at least one compartment through which thedoctor blade material from the roll situated in said compartment isunwound.
 2. The arrangement of claim 1 , further comprising ameasurement detector arranged in each of said at least one compartmentproximate said opening to measure the length of doctor blade materialbeing unwound from the roll situated in said compartment.
 3. Thearrangement of claim 1 , wherein said cutting means comprising a cut-offdevice arranged proximate said opening of each of said at least onecompartment, further comprising guide means associated with each of saidat least one compartment for guiding unwinding of the doctor bladematerial through said opening.
 4. The arrangement of claim 1 , whereinsaid cutting means comprising a cut-off device arranged proximate saidopening of each of said at least one compartment.
 5. The arrangement ofclaim 1 , further comprising guide means associated with each of said atleast one compartment for guiding unwinding of the doctor blade materialthrough said opening.
 6. The arrangement of claim 1 , wherein saidholding means comprise a carriage and at least one shaft mounted onbearings in said carriage, each of the at least one roll being arrangedon a respective one of said at least one shaft.
 7. The arrangement ofclaim 1 , wherein said holding means comprise a carriage, the at leastone roll comprising a plurality of rolls, said carriage including arespective compartments holding each of the rolls, said carriageincluding wheels for enabling movement of said carriage.